The population of DROC was estimated at 46.7 million in 1997. As many as 250 ethnic groups have been distinguished and named. The most numerous people are the Kongo, Luba, and Mongo. Although 700 local languages and dialects are spoken, the linguistic variety is bridged both by the use of French and the intermediary languages Kikongo, Tshiluba, Swahili, and Lingala.